The invention deals with a transmitting and receiving device for optoelectronic communication systems that contain electronic circuits housed in a metal case, and an opening in the outside wall of the metal casing for insertion of a glass optical fiber.
A device of this type is disclosed in TELCOM Report 2 (1979), supplement "Digital Transmission", at page 114.
For such transmitting and/or receiving devices it is often necessary to enclose a circuit module that has an optically coupled glass optical fiber in a hermetically sealed metal case. This requires a hermetically sealed lead-in for the glass fiber on the outside wall of the metal casing. This is especially important when unshielded semiconductor components are used.
A pigtail lead-in can be produced by bonding. However, this does not necessarily produce a hermetically sealed lead-in. A pressure seal imposes a relatively high mechanical stress on the fiber and is not sufficiently shock-resistant for many applications. Finally, experimentation has shown that soldering by applying a drop of solder may result in insufficient wetting of the glass fiber due to poor heat transfer on the fiber.